Patent GB-771551-A (GB)
Title: Improvements in or relating to methods of and apparatus for composing lettering for printing
IPC: G06F40/189
Filed: 1955-03-24
Abstract: 771,551. Strip-perforating apparatus; justifying type. BALFOUR G. P., BLANCHARD, A. R., and RAYMOND, F. H. March 24, 1955 [March 24, 1954; March 14, 1955], No. 8612/55. Class 100(3)  A method of composing lettering for printing comprises the production of a coded first record of the letters to be printed and an instruction record bearing service information (e.g. line measure, spaces. make-up instructions) and the automatic conversion of the first record and the instruction record to a coded second record, wherein the coded first record is suitable for the control of a calculating machine. and wherein the second coded record is suitable for the control of an automatic or semi-automatic composing machine. Apparatus for carrying out the method includes a calculating machine for the conversion of the first record to the second record. The first step is to prepare a coded perforated tape 1, Fig. 1, including lettering to be printed and service information (or separate tapes may be prepared for lettering and for service information), and plain language records 9 and 8, Fig. 4, of lettering and of service information. The tape 1 includes driving perforations 2, service information peforations j (following code indicates line measure), n (following code indicates line number in typewritten text), v (following code defines face and size of type), t (following codes indicate matter to be printed), b (space), a (beginning of paragraph), f (end of paragraph), d (control of entry of signals in the electronic calculator). Combinations of perforations (other than d) represent lettering, or numerals according to a binary code. The tape is perforated under the control of keyboards 3, 4 which at the same time produce plain language records 9, 8 by means of type arms 5, 6. The keyboard 4 is disconnected from the platen roller feed. so that service information on the page 8 (which is transparent) is in the same position as the previous letter on the page 9, and the pages can thus be read together by superposition with staggering of the line spaces. Special keys (which do not operate the type bars) are provided to produce the service information signals. The key N is associated with ten numeral keys for producing the line number, which is typed at the end of each line of text on both sheets 9 and 8, and punched in the tape according to the binary system. The key A also shifts the platen roller to the left a predetermined number of keys, and the key F to its left-hand position. Blanks are produced by a spacebar E. An end-of-line hyphen is produced by a key U. One keyboard alone could be used to produce one plain language record, a "service" key causing feed of the roller through half a line space so as to stagger the service information. It is also necessary to produce a "correction" tape, which is done by means of the same apparatus, and when any error occurs in the original record, the complete line containing the error,is repeated in its correct form together with the original line number. For producing the perforations, each key 10, Fig, 5, actuates two contacts, one 17 of which controls the feed of the tape past eight punches, and the other 16 of which operates one or more of the punches d, f, a, b, t, v, n, j to form the equivalent perforations. The next stage is to convert the codeded record (i.e. perforations in the tape) into electrical signals, which are then converted into signal combinations in a second record (e.g. perforated tape) for use in controlling a typecasting machine or photographic composing machine. The tape is fed past a scanning head. Fig. 6, comprising eight lamps 28 in a plane 29 and eight photo-electric cells 30. Each signal is produced in the form of a voltage pulse, by means of preamplifiers 31, at terminals j, n, v, t, b, a, f, d, and a pulse of reversed polarity, by means of a reversing stage 32, at terminals j, n, v, t, b, a, f, d. Two such scanning heads are provided, one for the main tape and one for the correction tape. The calculator, Fig. 7, comprises an input equipment E for reproducing the code information on the two tapes, an arithmetical operator OA, an output equipment S, and a programme equipment P which separately influences, the working of the equipment E. OA and S. The equipment E comprises two scanning heads 50, 51 provided with step-feed electromagnets 52. 53 fed by control pulses emanating from the programme, and applied at 54. An assembly 55 selects the head to be operated by disabling one of the electromagnets, and by means of its output terminals 58, 59 controls the conductivity of two gating circuits 60, 61 for transmission of the signals from the heads 50, 51 to a mixing circuit 62. The arrangement is such that the head 50 is in operation except when the line numbers in the parts of the two tapes being scanned are equal, when the head 51 for the correction tape comes into operation. The signals are then passed to an output circuit 63 and so to the equipment OA. The equipment OA comprises an input 64 leading through a routing circuit 66 to a calculating circuit 65 and through a gating circuit 67 to a memory 68. The results of the calculations are fed into memories 71, 72. The memories 68, 71, 72 feed an equipment 73 also controlled by the programme, and an output 75, whence the results pass to the equipment S. The equipment S comprises an input 76 a matrix 79 which converts the signals into other signal combinations, and at least one recording head 77 conrolled by a step-feed electromagnet 78, whereby the final control tape is produced. The operating programme of the calculator is as follows:-Signals are introduced representing letters and spaces of a manuscript together with their "weighting values," that is, the.number of typographical measuring units to be allotted to each. The calculator will then take a set of the closest value short of the desired line measure J, namely L. It will then verify how many justifying spaces exist in the set (N), and effect the usual division (J-L)/N=Q+R, then adding Q + 1 units to R spaces and Q units to (N-R) spaces, so as to justify. It is, however, a function of the programme to ensure that the calculator does not justify a line with the last word broken, unless it is permissible in the language concerned to break the word at that point. For this purpose, a list of prohibitions is introduced into the memory of the programme. When a prohibition exists, further shortening takes place until the line ends at a point where it can be broken. In the case of a paragraph ending, the Q+1 and Q units must be added to the spaces in the length of line up to the end of the paragraph, and complementary spaces added to complete the line. Similarly, in the case of a paragraph beginning, the complementary spaces are added at the beginning. The calculator is conditioned to perform these operations.